In a supercharging apparatus of a vehicle, which includes a turbocharger, intake air is pressurized through use of exhaust energy of an internal combustion engine. Therefore, when the exhaust energy is decreased, a boost pressure is decreased. That is, in a case where the flow quantity of the exhaust gas is small, or the temperature of the exhaust gas is low, the boost pressure is decreased. Thus, at the time of depressing an accelerator pedal with a foot of a driver of the vehicle to accelerate the vehicle, turbo lag may possibly be generated to deteriorate the drivability.
For instance, JP H05-321804A proposes a technique of shortening the turbo lag by increasing the exhaust energy at the acceleration time.
The technique of JP H05-321804A increases the exhaust energy by retarding the ignition timing.
However, when the ignition timing is retarded from the appropriate timing, the combustion of the appropriate timing cannot be achieved. Thus, the output torque of the engine is reduced, and the drivability is deteriorated. Furthermore, the fuel consumption is also deteriorated.